1. Field of the Invention
The present invention relates to an automatic deboning method and apparatus for an upper half of a poultry carcass for meat (hereinafter simply referred to as upper half) in which organic tissue such as tendons around a shoulder joint is severed, and breast meat is separated together with wings from a bone and white meat are easily removed from a bone, and particularly, to an automatic deboning method and apparatus for an upper half of a poultry carcass in which an upper half can automatically be deboned without no human hands realizing a high recovery rate in a flexible manner regardless of a size of the upper half.
2. Description of the Prior Art
In recent years, breeding, slaughtering and deboning of carcasses of poultry for meat have been grown to a large scale in the related industry and various types of automation have actually been practiced.
While separation of thigh meat from a carcass of poultry for meat is currently performed by human hands, a deboning method and apparatus suitable for separated thigh meat have been proposed by the same inventors as those of the present invention.
Meanwhile, heretofore, breast meat has also manually been stripped from an upper half which is a remainder after the thigh meat is cut off from the carcass of poultry for meat, but there have still been problems that foreign matter is apt to be mixed into breast meat and white meat is left behind between forked branches of a furcula in a severing process, and in addition, breast meat and white meat are subject to damages in each stripping operation, which devaluates the meats as an article of commerce. A worker performs severing and stripping, necessarily putting a palm and a finger in direct contact with meat, which has lead to other problems that a recovery rate is reduced and a management cost in a hygienic aspect becomes higher.
Therefore, the inventors of the present invention has conducted an analysis on an organic configuration of the upper half of a poultry carcass, considering that reduction in a recovery rate in the conventional deboning means is caused by being fully bound by the conventional way without any understanding of configuration of an organic upper half.
An organic configuration which has been apparent through the analysis is, as seen in perspective views of FIGS. 16, 17, such that muscle of the white meat 112 is connected with humeruses which are respectively combined with the glenoids 101a which the scapula heads 101 contain, while the breast meat 109 is connected with the scapula head 101 through breast muscle, and wings 107 are connected with the scapula head 101 through upper arm muscle, and the breast muscle 109 is formed in a space surrounded by the scapula 102, the upper portion of an os coracoideum 106 and the furcula 103.
As can be seen in FIG. 17, the scapula heads 101 at which the furcula 101, the os coracoideum 106 and the scapula 102 are merged contains the glenoid 101a, a caput humeri, not shown, is fittingly engaged in the glenoid 101a, and the scapula head 101 and the caput humeri forms a shoulder joint, being coupled by a ligament, a tendon, a muscle, a joint envelop and the like.
In the case where breast meat or breast meat together with wings are separated, as shown in FIG. 17, the tendon, the ligament, the muscle, the joint envelop and the like which couple and engage the glenoid 101a of the scapula head 101 and the caput humeri (FIG. 19) with each other in the shoulder joint are cut off as a precondition (hereinafter referred to as shoulder joint line-cutting), and a recovery rate is greatly affected by whether performance of the shoulder joint line-cutting is good or not: that is if the position and depth of the shoulder line-cutting are properly set regardless of a size of the upper half, a good recovery rate is secured.
In order to execute good shoulder joint line-cutting, the insert position, cutting depth and cutting direction of a cutter are required to be properly set in a flexible manner according to a size of the upper half all the time.
A spatial relation between positions of tendons of organic tissue which are an object of the shoulder joint line-cutting operation and a size of an upper half has been studied in a detailed manner based on a skeletal structure, and as a result, the followings have been concluded:
1) That is, in FIGS. 18 (A), (B), (C), the skeletal structure of an upper half is shown in a front elevational view, side elevational view and rear elevational view, when seen from the breast side. In FIGS. 19 (A), (B), enlarged views of encircled portions marked by D and E respectively of FIGS. 18 (B), 18(C) are shown, which are a shoulder joint and its periphery.
The followings can be observed from FIGS. 19 (A), 19 (B):
1-a) The head 101 of the scapula 102 and the caput humeri 105 are coupled with two sets (1), (2) of tendons and thereby the caput humeri 105 is fittingly engaged in the glenoid 101a.
1-b) As seen from the rear elevational view shown in FIG. 9 (B), the set of tendons (1) are positioned outward of the set of tendons (2) and the set of tendons (1) are originated from the scapula head 100 and extended onto the caput humeri 105 outward off to the lower side, while the set of tendons (2) are also originated from the head 101 of the scapula and extended to a position roughly lower than the caput humeri 105, downward, inward and deeper.
The inventors of the present invention has already proposed separation of breast meat which automatically copes with a variety of sizes of upper halves of poultry carcasses, in consideration of an organic configuration of the upper half, structural positions of tendons around a shoulder joint and the like, which has been made clear as described above.
The case of the above proposal relates to a method of shoulder joint line-cutting which copes with sizes of upper halves which would otherwise entail reduction in a recovery rate, wherein a width between shoulder joints and a height thereof are restricted within predetermined dimensions. Hence, such a proposed method is accompanied with unnaturalness, and besides forces to accept troubles caused by stepwise restriction, so that the method could not be said a perfect measure.